A255027 - OEIS

A255027

T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with no 3x3 subblock diagonal sum 0 or 1 and no antidiagonal sum 0 or 1 and no row sum 0 or 1 and no column sum 0 or 1

26, 54, 54, 117, 134, 117, 269, 405, 405, 269, 601, 1121, 1489, 1121, 601, 1306, 3015, 5077, 5077, 3015, 1306, 2853, 8338, 17447, 21854, 17447, 8338, 2853, 6308, 23077, 60237, 92217, 92217, 60237, 23077, 6308, 13940, 63446, 206739, 391926, 480456

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OFFSET

1,1

COMMENTS

Table starts

....26.....54.....117.......269........601........1306.........2853

....54....134.....405......1121.......3015........8338........23077

...117....405....1489......5077......17447.......60237.......206739

...269...1121....5077.....21854......92217......391926......1669286

...601...3015...17447.....92217.....480456.....2547757.....13460633

..1306...8338...60237....391926....2547757....16789556....110131505

..2853..23077..206739...1669286...13460633...110131505....896763036

..6308..63446..711741...7114859...71027915...722619025...7301549016

.13940.174690.2455031..30309034..375675337..4749948369..59570598618

.30665.481563.8451157.129016023.1985308048.31181555198.485457428280

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..480

FORMULA

Empirical for column k:

k=1: a(n) = a(n-1) +3*a(n-3) +4*a(n-4) +4*a(n-5) +2*a(n-6) for n>7

k=2: [order 8] for n>9

k=3: [order 15] for n>17

k=4: [order 23] for n>25

k=5: [order 43] for n>45

k=6: [order 71] for n>73

EXAMPLE

Some solutions for n=4 k=4

..0..1..1..1..1..1....1..1..1..1..1..0....1..1..1..1..1..1....1..1..1..1..1..0

..1..1..1..1..1..1....1..0..1..1..1..1....1..1..1..0..1..1....1..1..1..0..1..1

..1..1..1..1..1..1....1..1..1..1..1..1....0..1..1..1..1..1....1..1..1..1..1..1

..1..0..1..1..1..1....0..1..1..1..0..1....1..1..1..1..1..1....0..1..1..1..0..1

..1..1..1..1..1..1....1..1..0..1..1..1....1..1..1..0..1..1....1..1..1..1..1..1

..1..1..1..1..0..1....1..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..0

CROSSREFS

Sequence in context: A042346 A042348 A042350 * A132767 A255020 A184839

Adjacent sequences: A255024 A255025 A255026 * A255028 A255029 A255030

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Feb 13 2015

STATUS

approved